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<html lang="en">

<head>
  <meta charset="UTF-8">
  <meta http-equiv="X-UA-Compatible" content="IE=edge">
  <meta name="viewport" content="width=device-width, initial-scale=1.0">
  <title>Document</title>
</head>

<body>
  <script>
    // 输出1~100岁
    // for (let i =1; i <= 100;i++){
    //   document.write(`${i}岁`)
    // }

    // for (let i =1; i <=100;i++){
    //   console.log(`${i}岁`);
    // }

// 求1~100之间的偶尔和
// let num = 0
//     for (let i = 1; i <=100;i++){
//       if (i%2 === 0){
//         num = num +i
//       }
//     }
    // document.write(num)
    // console.log(num);


//  求1~100之间偶数的和
   let num = 0
   for (let i =1; i<=100; i++){
       if(i %2 === 0){
           num = num + i
       }
   }
   console.log(num);
   

  </script>
</body>

</html>